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Reading that, how in the world could he think that that was the way to go and in what way, shape or form would clicking keys on a virtual keyboard instead of a real one make the movement of the characters smoother?

I just don't understand any of this, this kind of thinking is too alien for me to comprehend.

@Quwertzuiopp I think what the article doesn't quite state is that he had some gamemaker-type thing on that modified NES (probably just an engine for a simple platformer). At least that's the only thing that makes sense to me.

@RaceProUK How does that answer anything that I don't understand? I know he used a virtual keyboard in his "development environment", but how would producing it that way make the game play smoother on the console? Do you understand what I am getting at? How would using a trackball on the development system make the movement of characters on the game boy any smoother?

In fact, in some ways he believed it helped make for smooth movement of the characters [...]

It, very loosely, implies that he assumed that designing the game on the tight restrictions of a tool on the famicom would ensure that the game itself would be limited.

but that also removed complexity allowing him to focus on making a game rather than fighting the system or bugs.

Of course, this could be a misunderstanding of the interviewer or author, and he really meant that the tool itself was designed for making games and abstracted the need to design the movement himself. That makes a lot more sense to me as a developer, considering the he also said that he assumed games were made this way.

Consider someone assuming games were made by RPG Maker, and consider there was a version of RPG Maker that ran on SNES.

Just assume everything I say is satirical. I've added tags to indicate otherwise.

I believe the original talk was translated from Japanese so it is possible some stuff got mixed up in translation. This quote is from the article of the guy who translated it (I think):

Their development tools didn’t even have keyboard support, meaning values had to be input using a trackball and an on-screen keyboard. By modern standards, it’s unthinkable, and nobody would ever do it, but at the time, Sakurai was a 20-year-old rookie, so he just thought that was the way it was done. There were some benefits to this type of workflow, however: it made the data processing load easier, and so they were able to create a game that had a very smooth movement for a Game Boy game.

...which...yeah I don't know. Maybe he meant having to use the specific developer tool [the Famicom system with Game Maker] let them optimize the game more.